This invention relates to a tightening and sealing device which is especially applicable in the fastening of corrugated type roofing elements which, as is known, are attached to a series of bolts which are fixed to the beams on which the corrugated roofing is situated. The stems of the bolts extend through orifices made in the roofing elements. In present fastening devices, a washer fits on the stem, and a nut made from a material and having a hardness different from the washer, is threaded onto the stem and compresses the washer against the roofing element. Deformation of the washer having a hardness less than the nut occurs when the nut is screwed and tightened, thus sealing the orifice through which the stem of the bolt passes. Thus, on the one hand, fastening of the roofing element is achieved, and, on the other hand, atmospheric agents, such as water or wind, are prevented from passing through the orifice which is sealed due to the deformation of the washer.
In this presently employed device, it is necessary to screw the nut along the entire length of the threaded stud.